Wednesday, 29 September 2010

The security standard calls for a broad range of security measures, but beyond the use of firewalling, intrusion protection systems and anti-virus software, the understanding of the requirements and responsibilities of the merchant are very often poorly understood.

This guide simplifies the scope of the balance of PCI DSS measures to just four areas.
- File Integrity monitoring
- Event Log centralization
- Security Vulnerability scanning for device hardening
- Change Management process
Understanding and implementing measures to address these four areas will make any QSA happy and get you compliant - and keep you compliant - in no time at all.

File Integrity Monitoring
As a mandated dimension of the PCI DSS, FIM verifies that program and operating system files have not been compromised.

Why is this important? The principal benefit of using FIM technology is to ensure that malicious code has not been embedded within critical application and operating system files. The insertion of a 'backdoor' or Trojan into core program files is one of the more audacious and elegant forms of hacking, and also one of the most dangerous.

The PCI DSS (Payment Card Industry Data Security Standard) specifies the following "Deploy file-integrity monitoring software to alert personnel to unauthorized modification of critical system files, configuration files, or content files; and configure the software to perform critical file comparisons at least weekly" and also that for log files "Use file-integrity monitoring or change-detection software on logs to ensure that existing log data cannot be changed without generating alerts (although new data being added should not cause an alert)".
Contemporary compliance management technology will provide pre-defined templates for all folders and files that should be tracked for File-Integrity, also allowing you to specify additional program folders and files unique to your environment, for instance, your core business applications.

File Integrity Monitoring technology conducts an initial inventory of all filesystems specified and 'fingerprints' all files using secure hashing technology, generating a unique checksum for each file. The system will then audit all files being tracked on a scheduled basis every 24 hours (even though the PCI DSS calls only for weekly checks) with any changes, additions, deletions or modifications being reported to you.
The latest generation of File Integrity Monitoring software also operate in a 'live tracking' mode for ultra-secure environments where file changes are detected and reported in real-time.

Other options to consider are to track and identify actual changes to file contents, useful when tracking configuration files to provide you with a complete audit trail of change history - this can be applied to any form of files such as text and xml.

Continuous Vulnerability Scanning
All security standards and Corporate Governance Compliance Policies such as PCI DSS, GCSx CoCo, SOX (Sarbanes Oxley), NERC CIP, HIPAA, HITECH, ISO27000 and FISMA require Windows and Unix Servers, workstations, and firewalls, routers and switches to be secure in order that they protect and secure confidential data.

'Hardening' a device requires known security 'vulnerabilities' to be eliminated or mitigated. A vulnerability is any weakness or flaw in the software design, implementation or administration of a system that provides a mechanism for a threat to exploit the weakness of a system or process. For the PCI DSS, it is a requirement that all 'within scope' sites are scanned for vulnerabilities every quarter. This gets expensive in a large scale, multi-site estates, as well as being a time-consuming management overhead.

Perhaps the biggest issue is that the results of any scan are only accurate at the time of the scan - any configuration changes made after the scan could render devices vulnerable and in a worst case scenario, devices could be left vulnerable to attack for a 3 month period. The ideal solution is to continuously track configuration changes. This is the only real way to guarantee the security of your IT estate is maintained. Using continuous configuration tracking technology allows you at any time to see the Compliance Score of any server and which settings need to be changed to re-harden the config. Any changes made should be reported, including Planned Changes which should also be reconciled with the original Request For Change or RFC record.

Secure, Centralized Event Log Management
Log analysis is a key weapon in the fight against any cyberattack. By gathering logs from all unix and windows servers, applications and databases, firewalls and routers, the method and pattern of an attack can be understood. Identifying the method and source of any attack allows preventative measures to be continually improved. This is why all security policies place log retention at their core. PCI DSS compliance requires logs to be gathered and reviewed daily, and retained for at least one year. Similarly for GCSx Code of Connection or CoCo compliance - Audit logs recording user activities, exceptions and information security events are to be retained for at least 6 months.

For any compliance initiative, it will be necessary to gather logs from all
- Network Devices
- Windows, Unix and Linux servers
- Firewall or IPS and IDS devices, Email and Web Servers
- Database and Application servers - even IBM Mainframes
- All other potentially useful sources of log information

Although the scope of most compliance standards will be largely satisfied at this stage, far greater value can be extracted from Centralizing Event Logs. Contemporary event and audit log management technology ensures all event logs are analyzed and correlated automatically, applying a comprehensive series of rules pertinent to any Security or Governance policy. Any breach of compliance will be alerted immediately allowing pre-emptive action to be taken before a problem arises. The best log management solutions provide pre-defined rules templates, allowing you to be in control of compliance straight out of the box.

The following is a checklist of features available in today's best log management software -
- All Security and Governance Policies supported via pre-packed Compliance Rule Templates
- Real Time Security Warnings i.e. violation of file integrity monitoring rules
- PCI DSS and GCSx Code of Connection supported 'out of the box'
- Web-based Dashboard and integration with Servicedesk as standard
- Powerful, keyword-based Event Log mining across any combination of devices and applications
- Complete solution for all Security Information and Event Management (SIEM) requirements
The latest generation of centralized log server software allows you to focus on true exceptions and important events by masking off the sometimes overwhelming flood of logs. Use the pre-built Compliance Templates and build your own keyword and logic-based correlation rules, allowing you to manage what really matters to your organization from a security and compliance standpoint.

Change and Configuration Management
ITIL Best Practises identify Change Management as one of the key, central processes that should be understood and assimilated into an IT Service Delivery operation. Change Management as a process is intended to ensure that when changes are made, they are first verified as being completely necessary and adding some value to the organization, and if so, that changes are then well planned, documented and clearly communicated to ensure any potential negative impact from the change is understood and eliminated or minimized. The entire experience and knowledge of the enterprise is harnessed and greater efficiencies can be gained from 'one visit' fixes - i.e. a number of required changes can all be delivered during one planned maintenance window. A well maintained Configuration Management Database (CMDB) will often be used as a means of better understanding the 'downstream' effects of changes and or their impact on a number of critical business services.

Crucially for any organization subject to Corporate Governance-driven security standards, changes to any IT system can affect its security. Installing application updates may introduce new vulnerabilities and making any configuration change may also render systems less secure and more prone to a security breach. The latest change and configuration management software tracks all changes to your infrastructure, exposing all unplanned changes and reporting clearly on the intended - and uniquely, the actual outcome - of any planned change. All network device configurations are automatically and securely backed up, with the option to remediate any unauthorized configuration change. Server configurations are tracked against either pre-defined security policies or your own personalized policy, with any deviations highlighted.
And once firewalls, servers, workstations, switches and routers are all in a compliant state, you need to ensure they remain that way. The only way to do this is to automatically verify configuration settings on a regular basis. Why? Because unplanned, undocumented changes will always be made while somebody has the admin rights to do so - legal or otherwise! The configuration change tracking solution will alert you when any unplanned changes are detected as well as keeping an audit trail of planned changes, reconciled with the request for change details.

This provides a unique 'Closed-Loop Change-Management Safety Net' - when changes need to be made to a device it is vital to ensure that changes are approved and documented - we make this easy and straightforward, reconciling all changes made with the RFC or Change Approval record. An open API allows integration with most service/help desks or other change management systems to establish a link between the change approval process and the actual changes that are made.

Sunday, 19 September 2010

This will be useful for anyone who is tasked with ensuring their organisation is compliant with the PCI DSS, or anyone just interested in learning more about this subject.

NNT Customers include retailers such as UK-wide retailer Spar, but also organisations as diverse as an on-line gaming company and a worldwide Christian ministry. The fact is that any organisation handling payment card transactions will need to put security measures and procedures in place to safeguard cardholder and card data.

This webinar will explain in plain English the measures required in order to simply and cost-effectively navigate a PCI audit and focus on some of the areas which any QSA will tell you are usually among the more challenging such as

We will show you some new concepts such as “Closed-Loop Change Management” and the “Change Management Safety net”

During the session we will share our experience of working with some of our customers and their PCI challenges, and illustrate key points using a live demo system.

Register via this link now and for more information regarding PCI DSS compliance visit http://www.nnt.co/nnt-change-tracker-enterprise-for-retailers-and-other-organizations-handling-payment-card-transactions.html

There are a number of buzzwords being used in this area - Security Vulnerabilities and Device Hardening? 'Hardening' a device requires known security 'vulnerabilities' to be eliminated or mitigated. A vulnerability is any weakness or flaw in the software design, implementation or administration of a system that provides a mechanism for a threat to exploit the weakness of a system or process. There are two main areas to address in order to eliminate security vulnerabilities - configuration settings and software flaws in program and operating system files. Eliminating vulnerabilites will require either 'remediation' - typically a software upgrade or patch for program or OS files - or 'mitigation' - a configuration settings change. Hardening is required equally for servers, workstations and network devices such as firewalls, switches and routers.

How do I identify Vulnerabilities? A Vulnerability scan or external Penetration Test will report on all vulnerabilities applicable to your systems and applications. You can buy in 3rd Party scanning/pen testing services - pen testing by its very nature is done externally via the public internet as this is where any threat would be exploited from. Vulnerability Scanning services need to be delivered in situ on-site. This can either be performed by a 3rd Party Consultant with scanning hardware, or you can purchase a 'black box' solution whereby a scanning appliance is permanently sited within your network and scans are provisioned remotely. Of course, the results of any scan are only accurate at the time of the scan which is why solutions that continuously track configuration changes are the only real way to guarantee the security of your IT estate is maintained.

What is the difference between 'remediation' and 'mitigation'? 'Remediation' of a vulnerability results in the flaw being removed or fixed permanently, so this term generally applies to any software update or patch. Patch management is increasingly automated by the Operating System and Product Developer - as long as you implement patches when released, then in-built vulnerabilities will be remediated. As an example, the recently reported Operation Aurora, classified as an Advanced Persistent Threat or APT, was successful in infiltrating Google and Adobe. A vulnerability within Internet Explorer was used to plant malware on targeted users' PCs that allowed access to sensitive data. The remediation for this vulnerability is to 'fix' Internet Explorer using Microsoft released patches. Vulnerability 'mitigation' via Configuration settings ensures vulnerabilities are disabled. Configuration-based vulnerabilities are no more or less potentially damaging than those needing to be remediated via a patch, although a securely configured device may well mitigate a program or OS-based threat. The biggest issue with Configuration-based vulnerabilities is that they can be re-introduced or enabled at any time - just a few clicks are needed to change most configuration settings.
How often are new vulnerabilities discovered? Unfortunately, all of the time! Worse still, often the only way that the global community discovers a vulnerability is after a hacker has discovered it and exploited it. It is only when the damage has been done and the hack traced back to its source that a preventative course of action, either patch or configuration settings, can be formulated. There are various centralized repositories of threats and vulnerabilities on the web such as the MITRE CCE lists and many security product vendors compile live threat reports or 'storm center' websites.

So all I need to do is to work through the checklist and then I am secure? In theory, but there are literally hundreds of known vulnerabilities for each platform and even in a small IT estate, the task of verifying the hardened status of each and every device is an almost impossible task to conduct manually.
Even if you automate the vulnerability scanning task using a scanning tool to identify how hardened your devices are before you start, you will still have work to do to mitigate and remediate vulnerabilities. But this is only the first step - if you consider a typical configuration vulnerability, for example, a Windows Server should have the Guest account disabled. If you run a scan, identify where this vulnerability exists for your devices, and then take steps to mitigate this vulnerability by disabling the Guest Account, then you will have hardened these devices. However, if another user with Administrator privileges then accesses these same servers and re-enables the Guest Account for any reason, you will then be left exposed. Of course, you wont know that the server has been rendered vulnerable until you next run a scan which may not be for another 3 months or even 12 months. There is another factor that hasn't yet been covered which is how do you protect systems from an internal threat - more on this later.

So tight change management is essential for ensuring we remain compliant? Indeed - Section 6.4 of the PCI DSS describes the requirements for a formally managed Change Management process for this very reason. Any change to a server or network device may have an impact on the device's 'hardened' state and therefore it is imperative that this is considered when making changes. If you are using a continuous configuration change tracking solution then you will have an audit trail available giving you 'closed loop' change management - so the detail of the approved change is documented, along with details of the exact changes that were actually implemented. Furthermore, the devices changed will be re-assessed for vulnerabilities and their compliant state confirmed automatically.

What about internal threats? Cybercrime is joining the Organised Crime league which means this is not just about stopping malicious hackers proving their skills as a fun pastime! Firewalling, Intrusion Protection Systems, AntiVirus software and fully implemented device hardening measures will still not stop or even detect a rogue employee who works as an 'inside man'. This kind of threat could result in malware being introduced to otherwise secure systems by an employee with Administrator Rights, or even backdoors being programmed into core business applications. Similarly, with the advent of Advanced Persistent Threats (APT) such as the publicized 'Aurora' hacks that use social engineering to dupe employees into introducing 'Zero-Day' malware. 'Zero-Day' threats exploit previously unknown vulnerabilities - a hacker discovers a new vulnerability and formulates an attack process to exploit it. The job then is to understand how the attack happened and more importantly how to remediate or mitigate future re-occurrences of the threat. By their very nature, anti-virus measures are often powerless against 'zero-day' threats. In fact, the only way to detect these types of threats is to use File-Integrity Monitoring technology. "All the firewalls, Intrusion Protection Systems, Anti-virus and Process Whitelisting technology in the world won't save you from a well-orchestrated internal hack where the perpetrator has admin rights to key servers or legitimate access to application code - file integrity monitoring used in conjunction with tight change control is the only way to properly govern sensitive payment card systems" Phil Snell, CTO, NNT

See our other whitepaper 'File-Integrity Monitoring - The Last Line of Defense of the PCI DSS' for more background to this area, but this is a brief summary -Clearly, it is important to verify all adds, changes and deletions of files as any change may be significant in compromising the security of a host. This can be achieved by monitoring for should be any attributes changes and the size of the file.

However, since we are looking to prevent one of the most sophisticated types of hack we need to introduce a completely infallible means of guaranteeing file integrity. This calls for each file to be 'DNA Fingerprinted', typically generated using a Secure Hash Algorithm. A Secure Hash Algorithm, such as SHA1 or MD5, produces a unique, hash value based on the contents of the file and ensures that even a single character changing in a file will be detected. This means that even if a program is modified to expose payment card details, but the file is then 'padded' to make it the same size as the original file and with all other attributes edited to make the file look and feel the same, the modifications will still be exposed. This is why the PCI DSS makes File-Integrity Monitoring a mandatory requirement and why it is increasingly considered as vital a component in system security as firewalling and anti-virus defences.

Conclusion
Device hardening is an essential discipline for any organization serious about security. Furthermore, if your organization is subject to any corporate governance or formal security standard, such as PCI DSS, SOX, HIPAA, NERC CIP, ISO 27K, GCSx Co Co, then device hardening will be a mandatory requirement. - All servers, workstations and network devices need to be hardened via a combination of configuration settings and software patch deployment - Any change to a device may adversely affect its hardened state and render your organization exposed to security threats - file-integrity monitoring must also be employed to mitigate 'zero-day' threats and the threat from the 'inside man' - vulnerability checklists will change regularly as new threats are identified

Monday, 6 September 2010

Here's another innovation from NNT - We know that getting systems secure and compliant with the PCI DSS, GCSx Co Co, SOX, and other Security Standards can be a time-consuming and expensive process -

‘Hardening’ Server configuration settings is a key task - but how do you know where to start?

Once all key vulnerabilities have been mitigated, how do you know that any subsequent changes to configuration settings will not render servers vulnerable again?

How do you even know when settings have been changed?

To assist with understanding of this area we have commissioned a new whitepaper from Computer Weekly’s Steve Broadhead - "Device Hardening, Vulnerability Remediation and Mitigation for Security Compliance"